package com.guigu.qingcheng.utils;

import io.jsonwebtoken.Claims;
import io.jsonwebtoken.Jws;
import io.jsonwebtoken.Jwts;
import io.jsonwebtoken.SignatureAlgorithm;
import org.springframework.util.StringUtils;

import javax.servlet.http.HttpServletRequest;
import java.util.Date;

public class JwtUtils {
    //常量
    public static final long EXPIRE = 1000 * 60 * 60 * 24;//token过期时间
    public static final String APP_SECRET = "ukc8BDbRigUDaY6pZFfWus2jZWLPHO"; // 秘钥

    //生成token字符串的方法
    public static String getJwtToken(String id, String nickName) {
       String JwtToken = Jwts.builder()
                .setHeaderParam("typ","JWT")
                .setHeaderParam("alg","HS256")

                .setSubject("qingcheng_user")
                .setIssuedAt(new Date())
                .setExpiration(new Date(System.currentTimeMillis() + EXPIRE))

               // 设置token主体部分，存储用户信息
                .claim("id",id)
                .claim("nickName",nickName)

                .signWith(SignatureAlgorithm.HS256,APP_SECRET)
                .compact();

       return JwtToken;
    }


    /**
     * 判断token是否存在与有效
     * @param jwtToken
     * @return
     */
    public static boolean checkToken(String jwtToken) {
        if (StringUtils.isEmpty(jwtToken))
            return false;
        try {
            Jwts.parser().setSigningKey(APP_SECRET).parseClaimsJws(jwtToken);
        }catch (Exception e){
            e.printStackTrace();
            return false;
        }
        return true;
    }


    /**
     * 判断token是否存在与有效
     * @param request
     * @return
     */
    public static boolean checkToken (HttpServletRequest request) {
        try {
            String token = request.getHeader("token");
            if (StringUtils.isEmpty(token))
                return false;
            Jwts.parser().setSigningKey(APP_SECRET).parseClaimsJws(token);
        }catch (Exception e){
            e.printStackTrace();
            return false;
        }
        return true;
    }


    /**
     * 根据token获取会员id
     * @param request
     * @return
     */
    public static String getMemberIdByJwtToken (HttpServletRequest request) {
        String jwtToken = request.getHeader("token");
        if(StringUtils.isEmpty(jwtToken)) return "";
        System.out.println(jwtToken);
        Claims claims = Jwts.parser().setSigningKey(APP_SECRET).parseClaimsJws(jwtToken).getBody();
        return (String) claims.get("id");
}
}
